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authorMichael Niedermayer <michaelni@gmx.at>2011-09-25 23:30:25 +0200
committerMichael Niedermayer <michaelni@gmx.at>2011-09-25 23:30:25 +0200
commit537a9e5cc28fe55deedc30953737cff124ac570f (patch)
tree3ebcc12011b67905d09f439dc85421cb1834927c /libavcodec/vmdav.c
parent508e47a5751b063e5b3d1d6aceda8a19ad8b1d37 (diff)
parentd853e571ad5e7e12c6a68cfde390daced7d85fbb (diff)
Merge remote-tracking branch 'qatar/master'
* qatar/master: ppc: fix some pointer to integer casts ppc: fix 32-bit PIC build vmdaudio: fix decoding of 16-bit audio format. lavf: do not set codec_tag for rawvideo h264: check for out of bounds reads in ff_h264_decode_extradata(). flvdec: Check for overflow before allocating arrays avconv: use correct output stream index when checking max_frames avconv: remove fake coded_frame on streamcopy hack Conflicts: avconv.c libavcodec/h264.c libavcodec/ppc/asm.S libavcodec/vmdav.c libavformat/flvdec.c libavformat/utils.c Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/vmdav.c')
-rw-r--r--libavcodec/vmdav.c121
1 files changed, 79 insertions, 42 deletions
diff --git a/libavcodec/vmdav.c b/libavcodec/vmdav.c
index 6729af6af7..63ac33db59 100644
--- a/libavcodec/vmdav.c
+++ b/libavcodec/vmdav.c
@@ -465,9 +465,8 @@ static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
#define BLOCK_TYPE_SILENCE 3
typedef struct VmdAudioContext {
- AVCodecContext *avctx;
int out_bps;
- int predictors[2];
+ int chunk_size;
} VmdAudioContext;
static const uint16_t vmdaudio_table[128] = {
@@ -490,13 +489,23 @@ static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
{
VmdAudioContext *s = avctx->priv_data;
- s->avctx = avctx;
+ if (avctx->channels < 1 || avctx->channels > 2) {
+ av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
+ return AVERROR(EINVAL);
+ }
+ if (avctx->block_align < 1) {
+ av_log(avctx, AV_LOG_ERROR, "invalid block align\n");
+ return AVERROR(EINVAL);
+ }
+
if (avctx->bits_per_coded_sample == 16)
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
else
avctx->sample_fmt = AV_SAMPLE_FMT_U8;
s->out_bps = av_get_bytes_per_sample(avctx->sample_fmt);
+ s->chunk_size = avctx->block_align + avctx->channels * (s->out_bps == 2);
+
av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
"block align = %d, sample rate = %d\n",
avctx->channels, avctx->bits_per_coded_sample, avctx->block_align,
@@ -505,41 +514,33 @@ static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
return 0;
}
-static void vmdaudio_decode_audio(VmdAudioContext *s, unsigned char *data,
- const uint8_t *buf, int buf_size, int stereo)
+static void decode_audio_s16(int16_t *out, const uint8_t *buf, int buf_size,
+ int channels)
{
- int i;
- int chan = 0;
- int16_t *out = (int16_t*)data;
-
- for(i = 0; i < buf_size; i++) {
- if(buf[i] & 0x80)
- s->predictors[chan] -= vmdaudio_table[buf[i] & 0x7F];
- else
- s->predictors[chan] += vmdaudio_table[buf[i]];
- s->predictors[chan] = av_clip_int16(s->predictors[chan]);
- out[i] = s->predictors[chan];
- chan ^= stereo;
+ int ch;
+ const uint8_t *buf_end = buf + buf_size;
+ int predictor[2];
+ int st = channels - 1;
+
+ /* decode initial raw sample */
+ for (ch = 0; ch < channels; ch++) {
+ predictor[ch] = (int16_t)AV_RL16(buf);
+ buf += 2;
+ *out++ = predictor[ch];
}
-}
-static int vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data,
- const uint8_t *buf, int silent_chunks, int data_size)
-{
- int silent_size = s->avctx->block_align * silent_chunks * s->out_bps;
-
- if (silent_chunks) {
- memset(data, s->out_bps == 2 ? 0x00 : 0x80, silent_size);
- data += silent_size;
- }
- if (s->avctx->bits_per_coded_sample == 16)
- vmdaudio_decode_audio(s, data, buf, data_size, s->avctx->channels == 2);
- else {
- /* just copy the data */
- memcpy(data, buf, data_size);
+ /* decode DPCM samples */
+ ch = 0;
+ while (buf < buf_end) {
+ uint8_t b = *buf++;
+ if (b & 0x80)
+ predictor[ch] -= vmdaudio_table[b & 0x7F];
+ else
+ predictor[ch] += vmdaudio_table[b];
+ predictor[ch] = av_clip_int16(predictor[ch]);
+ *out++ = predictor[ch];
+ ch ^= st;
}
-
- return silent_size + data_size * s->out_bps;
}
static int vmdaudio_decode_frame(AVCodecContext *avctx,
@@ -547,10 +548,13 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
+ const uint8_t *buf_end;
int buf_size = avpkt->size;
VmdAudioContext *s = avctx->priv_data;
- int block_type, silent_chunks;
- unsigned char *output_samples = (unsigned char *)data;
+ int block_type, silent_chunks, audio_chunks;
+ int nb_samples, out_size;
+ uint8_t *output_samples_u8 = data;
+ int16_t *output_samples_s16 = data;
if (buf_size < 16) {
av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
@@ -566,13 +570,16 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
buf += 16;
buf_size -= 16;
+ /* get number of silent chunks */
silent_chunks = 0;
if (block_type == BLOCK_TYPE_INITIAL) {
uint32_t flags;
- if (buf_size < 4)
- return -1;
- flags = AV_RB32(buf);
- silent_chunks = av_popcount(flags);
+ if (buf_size < 4) {
+ av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
+ return AVERROR(EINVAL);
+ }
+ flags = AV_RB32(buf);
+ silent_chunks = av_popcount(flags);
buf += 4;
buf_size -= 4;
} else if (block_type == BLOCK_TYPE_SILENCE) {
@@ -581,11 +588,41 @@ static int vmdaudio_decode_frame(AVCodecContext *avctx,
}
/* ensure output buffer is large enough */
- if (*data_size < (avctx->block_align*silent_chunks + buf_size) * s->out_bps)
+ audio_chunks = buf_size / s->chunk_size;
+ nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) / avctx->channels;
+ out_size = nb_samples * avctx->channels * s->out_bps;
+ if (*data_size < out_size)
return -1;
- *data_size = vmdaudio_loadsound(s, output_samples, buf, silent_chunks, buf_size);
+ /* decode silent chunks */
+ if (silent_chunks > 0) {
+ int silent_size = avctx->block_align * silent_chunks;
+ if (s->out_bps == 2) {
+ memset(output_samples_s16, 0x00, silent_size * 2);
+ output_samples_s16 += silent_size;
+ } else {
+ memset(output_samples_u8, 0x80, silent_size);
+ output_samples_u8 += silent_size;
+ }
+ }
+
+ /* decode audio chunks */
+ if (audio_chunks > 0) {
+ buf_end = buf + buf_size;
+ while (buf < buf_end) {
+ if (s->out_bps == 2) {
+ decode_audio_s16(output_samples_s16, buf, s->chunk_size,
+ avctx->channels);
+ output_samples_s16 += avctx->block_align;
+ } else {
+ memcpy(output_samples_u8, buf, s->chunk_size);
+ output_samples_u8 += avctx->block_align;
+ }
+ buf += s->chunk_size;
+ }
+ }
+ *data_size = out_size;
return avpkt->size;
}